Myasthenia gravis is a rare disease, and our hospital, under the leadership of Professor Deng Tietao, a national medical master, has accumulated a lot of experience in treating such patients for a long time. Minimally invasive surgery is an important means to treat myasthenia gravis. After domestic and foreign study, our department has successfully carried out enlarged thymectomy and thymoma resection not through the chest but through the epigastric subsynovial thymus, which does not damage the chest tissue and only requires 1.5 cm subsynovial incision and 0.5 cm subcostal incision on both sides to complete the operation, which is less traumatic to the patient and especially protects the integrity of the thorax better for patients with myasthenia gravis, with mild postoperative pain and faster recovery of respiratory function. Minimally invasive! Greater benefit for the patient!